IADR Abstract Archives
Stress Analysis of Implant-Supported Crowns Made of Different Materials.
Objectives: The objective of the present finite element analysis (FEA) was to determine the distribution and transmission of stress in implant-supported crowns made of different restorative materials.
Methods:
Based on the STL data of a molar crown (tooth 46), a standardized titanium implant replica (type Tissue Level Straumann, CH) and a simulated human mandible (BodyParts3D/ Anatomography, Database Center for Life Science, J), a model was created for the present FEA using reverse engineering (Fusion 360 and Meshmixer, Autodesk, USA). The mandible was divided into cancellous bone and compacta. In addition to the above structures, a cement gap of 100 µm was created for adhesive cementation (Panavia F 2.0, Kuraray, J). The calculation was performed for four different superstructures made of composite (Grandio Bloc, VOCO, D), PICN (Enamic, Vita Zahnfabrik, D), lithium disilicate (emax Press, Ivoclar Vivadent, FL) and zirconia (emax ZirCAD, Ivoclar Vivadent, FL). The load was applied via an oxide ceramic ball (d=12 mm) by means of a forced displacement of 8 µm in the occluso-apical direction. Linear-static simulation was performed using Fusion 360 CAE software (Autodesk, USA). All components were investigated with respect to von Mises equivalent stresses and the occurring displacement.
Results: Stress maxima ranged between 561.9 MPa (zirconia) and 219.3 MPa (composite) in the region of the restorative materials and 79.6 MPa (zirconia) and 4.3 MPa (composite) in the osseous structures.
The reaction forces in the area of the oxide ceramic sphere ranged between 106.3 N (composite) and 259.6 N (zirconia). Materials with high elastic moduli (zirconia, lithium disilicate) exhibited higher von-Mises stresses in all components and produced higher reaction forces than the resin-based materials.
Conclusions: FEA showed a stress development that was dependent on the material of the superstructure and the conditions of the FEA analysis. Under the present conditions with a forced displacement, resin crowns caused lower stress in the area of the implant and the osseous structures.
Methods:
Based on the STL data of a molar crown (tooth 46), a standardized titanium implant replica (type Tissue Level Straumann, CH) and a simulated human mandible (BodyParts3D/ Anatomography, Database Center for Life Science, J), a model was created for the present FEA using reverse engineering (Fusion 360 and Meshmixer, Autodesk, USA). The mandible was divided into cancellous bone and compacta. In addition to the above structures, a cement gap of 100 µm was created for adhesive cementation (Panavia F 2.0, Kuraray, J). The calculation was performed for four different superstructures made of composite (Grandio Bloc, VOCO, D), PICN (Enamic, Vita Zahnfabrik, D), lithium disilicate (emax Press, Ivoclar Vivadent, FL) and zirconia (emax ZirCAD, Ivoclar Vivadent, FL). The load was applied via an oxide ceramic ball (d=12 mm) by means of a forced displacement of 8 µm in the occluso-apical direction. Linear-static simulation was performed using Fusion 360 CAE software (Autodesk, USA). All components were investigated with respect to von Mises equivalent stresses and the occurring displacement.
Results: Stress maxima ranged between 561.9 MPa (zirconia) and 219.3 MPa (composite) in the region of the restorative materials and 79.6 MPa (zirconia) and 4.3 MPa (composite) in the osseous structures.
The reaction forces in the area of the oxide ceramic sphere ranged between 106.3 N (composite) and 259.6 N (zirconia). Materials with high elastic moduli (zirconia, lithium disilicate) exhibited higher von-Mises stresses in all components and produced higher reaction forces than the resin-based materials.
Conclusions: FEA showed a stress development that was dependent on the material of the superstructure and the conditions of the FEA analysis. Under the present conditions with a forced displacement, resin crowns caused lower stress in the area of the implant and the osseous structures.